CHUCK DEVICE

PURPOSE:To provide a chuck device which reliably holds a work in a desired position and prevents the end face of a work from levitation from a reference plane. CONSTITUTION:Claw members 10 are arranged to a body part 20 in a manner to be positioned facing a plurality of respective guide parts 22 arranged toward the axis of the body part 20. By extending a plurality of the claw members 10 along the guide part 22, the claw members are reciprocated toward the axis of the body part 20. By interlocking a plurality of the claw members 10 such that the claw members are caused to effect approximately the same reciprocation, the work 1 is held as centering of the work 1 is carried out. In a so formed chuck device, the guide part 22 has a gradient relative to a surface which crosses the axis of the body part at right angles.